The research topic explores the relationship between tree age and photosynthetic variables. The trees from which data were recorded are three species of maples: Acer miyabei, Acer rubrum, and Acer truncatum x Acer platanoides. The planting dates of the three species were 2008, 2007, and 1993, respectively. These topics are of interest due to their environmental relevance with the current state of habitat destruction in the world. The photosynthetic variables researched were photosystem II efficiency and chlorophyll content. Higher photosystem II efficiency relates to higher outputs of oxygen, and higher chlorophyll content in older species of trees could be an indicator of a tree’s survival ability, both of which show the importance of preserving natural habitats. Previous work concludes that larger trees, and therefore older trees, had increased photosynthesis with age (Bond, 2000). Yet, Day et al. (2001) found that Picea rubens had age related decreases in photosynthetic rates. With this research, the effect the species of a tree within the same family has on photosystem II efficiency and chlorophyll content can be seen. Also, it can be seen if tree age causes photosystem II to become more efficient, and if tree age causes chlorophyll content to remain higher longer into the fall. It was hypothesized that trees within the same family, but with different species, should have very similar phi II efficiencies and chlorophyll content. As trees age, it is hypothesized that photosystem II becomes more efficient, because they have adapted to their environment as they aged. Also as trees age, it is hypothesized that chlorophyll content remains higher longer into the fall, because the tree is able to survive better at an older age. If these hypotheses are supported, it will show the importance of preserving habitats with not only older trees, but all trees, because as trees age they will have higher outputs of oxygen and will become better adapted to survive their environment. For future studies, testing chlorophyll content and phi II in the same trees in this study now within warm, summer climates compared to the data obtained from these trees in the cooler fall/winter climates. Studying how, or even if, the cold has any effect on the production of chlorophyll and phi II would be something to investigate and relate back to the current experiment. Random Sampling Method:Photosynq multispec device #120. Six individual maple trees of three different ages, and three different species, were studied on the Michigan State University campus. The trees planted in 2007 were Acer miyabei, the trees planted in 2008 were Acer rubrum, and the trees planted in 1993 were Acer truncatum x Acer platanoides. For each individual tree, twenty samples were taken on each day of data collection, totaling 120 samples for all six trees in one day. Random sampling was completed by taking five samples from each quadrant of the tree (northeast, northwest, southeast, and southwest) to total the twenty samples for a single tree. A stepstool was used to reach the leaves that were higher up on the trees. The devices that were used to record and collect the data were the photosynq MultiSpeQ device, and the android device. The MultiSpeQ device, according to Kuhlgert et al. (2016), is useful for collecting photosynthetic parameters. It collects plant phenotype data and transmits it to the android device. From there the data goes to the photosynq website, where it is stored and can be analyzed. All data collected were continuous ratio data. The two trees in each age group were biological replicates, and the two data collections each week were technical replicates. This data will be analyzed with a t-test for each of the age groups since there are two trees for each age group, and an ANOVA, analysis of variance, statistical analysis for all six individual trees. The t-test will verify that there are no significant statistical differences between the two trees of the same age, while the ANOVA analysis will compare all of the trees in the study to see if there are any significant statistical differences of ΦII or chlorophyll content between the age groups.
- Leaf Photosynthesis - MultispeQ Beta ONLY
Measures photosynthesis-related parameters in <15 seconds, including: Phi2, PhiNPQ, PhiNO, NPQt, qL, LEF, and SPAD. In addition, measures PAR (photosynthetically active radiation), ambient temperature and relative humidity.
Works with the MultispeQ Beta device only
- What tree are you observing leaves from? (Multiple Choice)
- What is the planting date of the tree? (Multiple Choice)
- What is the species you are testing? (Multiple Choice)
- What quadrant are you testing from? (Multiple Choice)
- What leaf sample are you taking? (Multiple Choice)